Patching-potholes is a widely practiced process, particularly in areas where ground freezes. Potholes develop as moisture below a road freezes, lifting a part of the road. That leaves the previously frozen portion unsupported and traffic may break the road. Potholes develop, which may be enlarged by further traffic. Patching is ordinarily done by a crew of three, a driver and two men with shovels who shovel cold patching material into the potholes from the back of a truck. When the potholes are filled with the cold patch material, it is left to traffic to pack the material in the holes. In fact, traffic lifts the material from the holes, resulting in a quick recreation of the potholes.
When potholes are partially filled or are not sealed or are improperly sealed, moisture collects in the holes. The moisture creates the freeze-thaw cycle in the following cold season. Often the same potholes reopen in the spring.
Patching potholes is slow, expensive and difficult work and requires a three-man crew.
Some attempts have been made to provide small independent pothole-patching vehicles, without success.
Reduction of crew required for patching potholes is a constant goal of governments who are charged with the maintenance of roadways.
The complexities of scheduling and the expense of three-man crews dictate that better, less labor-intensive methods be found for pothole patching.